1. Field of the Invention
Embodiments of the present invention generally relate to managing images pertaining to digital microscopy and, more specifically, to a method and apparatus for simulating depth of field (DOF) in digital microscopy.
2. Description of the Related Art
A digital microscope images a specimen at different depths to create a sequence of digital images. Each image represents a portion of the specimen at a particular depth of focus. Thus, at a certain depth, only a fraction of the entire specimen is in focus. The sequence of digital images is stacked along a Z dimension corresponding to depth, referred to as a Z-stack. Each image in a Z-stack is focused at a different depth in the captured specimen. The Z-stack can also be simulated through the use of an all-focus image and a depth map of the specimen. The simulation offer a very low-bandwidth approximation to the original z-stack, while retaining the depth-dependent blurring and feel of the original data, and may help in various Z-stack data compression schemes.
Simulating DOF in microscopy poses numerous problems which are not fully addressed by the current technology. According to one attempt at simulating DOF, indirect use of the Z-stack is disclosed, by using a model for image formation as a spatially varying two-dimensional convolution with the system's point spread function (PSF), where the PSF is modeled using a Gaussian-shaped filter. However, in this approach, the computational complexity is high due to the spatially varying nature of the procedure. Complexity is further increased due to the large spatial support of the filters required to achieve a satisfactory out-of-focus blurring. Other conventional approaches generally require a trade-off between quality and complexity. In one such conventional approach, simulating DOF for artificial computer-generated scenes require the result to be of high graphical quality, which is achieved at the cost of high complexity.
Thus, there is a need for method and apparatus for simulating depth of field (DOF) in microscopy.